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Topic: How long can I let a yeast cake sit before reuse? (Read 5357 times)

How long can I let a yeast cake sit before reuse? I just brewed a nice IPA (w magnum, summit, simcoe, cascade, and citra) using Wyeast 1056 (American Ale). The fermentation buckets are still in the fermentation fridges (at 65 F or colder). I might not be able to brew for another 5-6 days from now.

The yeast cake is just sitting in the bucket. I just kegged and bottled last night. I put the lid back on and put it in the fridge.The OG was 1.070 (or 1.075, I can't recall off-hand), FG was 1.012.

I'm debating whether to call it an American IPA (14B) or Imperial IPA (14C) for comp purposes. The flavor and aroma are awesome and prominent, but not excessive. And the bitterness is ideal/not excessive for an IPA.

I'll double check the OG on the brew sheet when I get home. In your opinion, if the OG was under 1.070, then would it be OK to use the yeast cake? Would you just clean the dried krausen off the walls of the bucket (aseptically, of course) and dump wort on top of the cake, or transfer the cake to a Mason jar or another vessel (and make a starter w yeast nutrients and energizers) and start over with a cleaned and sanitized bucket?

I normally wouldn't be so lazy and take such risks, but we're a sports-minded family and we're in the middle of football conditioning 2-3x/week, morning or evening swim practices/meets and practically daily baseball tournaments (a few weeks ago we did 28 games in 23 days) and I'm really pressed for time. But, I must brew--I like the brews at the end of a long day and being able to offer a keg at the victory parties at the end of the season.

when i've reused a WHOLE yeast cake i've made a 1040ish beer and then come back and racked a bigger beer on top of it, like 1080ish. i've done this twice and it's worked fine for me, although i wouldn't say it's the best practice. i'll typically rinse yeast and make a starter again. if you're in a crunch for time, i wouldn't rack a beer on top of this cake, i'd save the brew day for another day when you can pitch the right amount of yeast...it's never fun to squeeze in a brew day in a few hours only to turn out beer that didnt' live up to your standards....i think this is also why a lot of people keep extra packets s-05 and notty around, for in a pinch circumstances. of course, you could toss all this out, go for it, and see how your beer comes out, although if you're brewing a smaller gravity and not as high hopped beer..i'd be a bit skeptical about how the beer would turn out.

Got home and checked the brew sheet. Est OG was 1.073; Hit 1.075. Est FG was 1.017; Hit 1.012.We'll see about using the yeast cake. I have a Wyeast 1056 yeast starter going now, just in case. So, between the cakes and the starter, I should be fine. Now, I just need time for a brew day.

1.070 is pretty high. Personally, I wouldn't reuse a yeast from a beer that high...others may disagree.

I am definitely one who disagrees.I've been reusing yeasts and going from average to strong and back to average (and back again several times over) for nearly 20 years. I stope these days after 7 or 8 repitches, but overall have not detected any performance issues, or off flavors.

I've reused yeast that high. On some beers it worked fine on others the results were not as predictable. Cleaner strains can tend to throw more esters and more estery strains can tend to get cleaner. I wouldn't say I ever had a bad batch from reusing yeast that high, just not as predictable.

I would NOT use yeast that has been sitting around for days in a bucket - however. The more o2 that you allow in the head space the more chance you have of picking up an acetobacter infection. I have seen it happen in only a matter of 48 hours when I have left yeast sit in the bottom of a bucket or carboy. YMMV.

professor and major, can you expand on what you do? when you go back and forth are you rinsing the yeast and then creating a new starter everytime? to me, it sounds like the OP was just going to toss a batch on top of an existing yeast cake, i'm assuming you guys aren't doing that.

I'm not too worried about esters and fruitiness (the yeast cake is from a citrusy/fruity IPA that used magnum, summit, simcoe, citra, and cascade)--I was thinking about making an American Wheat with the yeast cake (and you know how people just love to put fruit slices in their glass of wheat beer).

in re Acetobacter--I kept the lid of the carboy on during transfer via the fermenting bucket spigot. I hadn't given that much thought. Obviously some air had to come into the bucket to equalize the pressure, and I did do it in my hot Florida garage so it is possible that some wild airborne bacteria or yeast could have snuck in there. Once I was done transferring, I secured the lid tightly and put it right back into the refrigerator (now at 40F). I wonder if the residual IBUs within the slurry will be enough to keep the acetobacter from taking hold--there's not much sugar for it to eat (i.e., dextrins/unfermentables) since I mashed at lower temps (151 F)--it's pretty dry.